1. Field of the Invention
The present invention relates to an axial fan and an electronic device including the same.
2. Description of the Related Art
Axial fans whose housings include slits have been known. For example, World Intellectual Property Organization Publication No. 2009/057063 discloses one such conventional axial fan. This conventional axial fan includes an impeller in which a plurality of blades are arranged in a circumferential direction about a central axis, and a housing (i.e., a wind tunnel portion) arranged radially outward of the impeller to surround the impeller. The housing includes a plurality of slits that are arranged in the circumferential direction and arranged to extend through the housing from an inner circumferential surface to an outer circumferential surface thereof.
The conventional axial fan as described above is often used as a cooling fan for an electronic device or the like, and is often attached to an exhaust duct provided in a casing of an electronic device or the like to define an air channel in the casing. In this case, the axial fan is sometimes attached to the duct such that an outer circumference of the axial fan is covered by a surface of the duct depending on the shape of the duct. In this case, the slits will be covered by the presence of the surface of the duct on the outside of the axial fan. When this happens, inflow of air into the housing through the slits is blocked, which thus makes it impossible to increase an air volume in a surge range, that is, resulting in a failure to make the most of an air intake effect of the slits.